Pbih timg-telegsiaph keceivbe



H. V. GROTJOHANN.

PRINTING TELEGHAPH RECEIVER.

APPLICATION FILED MAY lo. |918.

LQ. PatentedJun 3, 1919.

6 SHEETS-SHEET l.

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i -M l |111) E 1709 y/a \AA 729 H. V. GROTIOHANN.

PRINTING TELEGHAPH RECEIVER.

APPLICATION FILED MAY IOI IQIB.

Patented June 3, ISIIII 6 SHEETS-SHEET lim: 1I

IIIIIIII" el? v :lum 1 III Wai/526%;

H. V. GROTJOHANN.

PRINTING TELEGRAPH RECEIVER.

APPLICATION HLED MAY 10. 1918.

Q@ Patented June 3, 1919.

6 SHEETS-SHEET 3.

I d@ I@ H. V. GROTJOHANN.

PRINTING EELEGRAPH RECEIVER.

AFPUCATIN FILED MAY 10, 918. p. PaEenEedJune 3,1919.

6 SHEETSASHEET 4.

H. V. GROTIOHANN.

PRINTING TELEGRAPH RECEIVER.

APPLICATION FILED' MAY l0. I9I8.

Patent-ed June 3, 19H).

6 SHEETS-SHEET 5 iff H. V. GROTIOHANN.

PRINTING IELEGIIAPII RECEIVER.

APPLICATION FlLED MAY l0. 1918. LSB Patented June 3,1919.

6 SHEETS-SHEET 6A www HARRY V. GRQTJOHANN, 0F CHCA, XLLN'OS, ASSIGNOR T0 GEORGE D. ROSE, 0F CHCGG, ELLENGES.

EBINTING-TELEGRPH RECEIVER.

To all whom it may concern:

Be it known that l, HARRY V. Geoinfo- HANN, a citizen of the -United States, resi dent at Chicago, in the county of Coo-k and State of illinois, have invented certain new and useful improvements in Printing-Tel- I egraph Receivers, of which the following is proved and the maintenance cost is reduced;

Second: to provide novel means for controlling the means for retracting the type wheel and for controlling the paper feeding means;

Third: to provide means for preventing the type wheel carriage from advancing beyond a predetermined position; and

Fourth: to provide a novel circuit arrangement for controlling the retracting magnet.

Further objects will appear as the descrip tion progresses, reference being had to the accompanying drawings, in which:

Figure 1 is a side elevation of a printing telegraph receiver embodying my invention;

Fig. 2 is a plan view thereof;

Fig. 3 is a transverse section taken on the line 3 3 of Fig. 1;

Fig. 4- is a transverse section taken on the line fir- 4 of Fig. 1;

F ig. 5 isa transverse section taken on the line 5 5 of Fig. 1;

l? ig. 6 is a transverse section taken on the line 6 6 of Fig. 2;

Fig. 7 is a detail side elevation of the stop :mechanism for the type wheel carriage; and

l? ig. 8 is a diagrammatical view showing the control magnets and certain portions of the control mechanism.

The sectional views are taken looking in the direction of the small arrows, and similar characters of reference refer to similar parts in the several drawings.

51s indicated above the objects of my inspecicetion ot Letters Patent.

.ppliceton filed 2day 16, 1918. Serial Ito. 233,653.

Patented June 3, 19119.

vention are to provide improvements in certain features of printing telegraph receivers now in use and in order properly to illustrate these features l have illustrated them in connection with a receiver of more or less conventional structure. Certain features of construction of the receiver illustrated in the drawings are found in the patent to Joy, 780,664, January 24, 1905.

rThe reference character 10 indicates the base plate of the receiver which supports two end plates 11 and 12 respectively and two intermediate brackets 13 and 14E respectively. The brackets 141 are connected by a brace rod 15. Rotatably mounted in the base plate 10 and a. bracket 16, extending inwardly from the end plate 11, is a power shaft 17 which is driven by means of a suit able motor 18, as shown in Figs. 1 and 6. The motor 18 may be of any desired type and is conventionally illustrated as being an electric motor.

The receiver comprises in general a type wheel and means for rotating this type wheel to select the desired character to be printed, means for advancing the type wheel space by space in order te properly space the printed characters, means for retracting the type wheel when it has reached the end of a line, a platen co-acting with the type wheel to print the selected characters, means for feeding paper between the platen and the type wheel with a step by step movement so as to properly position the lines of the printed matter, and means for properly controlling the various means recited above. r1`hese various Ameans will be described in substantially the order enumerated.

rirhe reference character 19 indicates the' type wheel which is splined upon the type wheel shaft 20 so as to move longitudinally thereof, and rotate therewith. T he type wheel shaft 20 is driven by means of a worm wheel 21 which is rotatably mounted upon the shaft 2() but has frictional engagement with the friction disk 22, which is mounted upon the shaft 20 and secured to one end of the tension spring 23. rihe other end of the tension spring 23 is secured to the shaft 20 by means of a collar 2e and a set screw 25. Movement of the worm wheel 21 toward the right is prevented by a collar 26 which is secured to the shaft 20 by a set screw 27.

lformed integrally with the gear 33.

From the above description 1t will be clear that when the worm wheel 21 1s rotated in a clockwlse direction (see Fig. 3)

vit will place the spring 23 under tension and means of an escapement wheel and lever 28.

and 29 respectively. in a manner well known to those skilled in this art, and illustrated and described in the patent to Joy referred to above. The oscillations of the escapement lever 29 are produced by the polarized escapement magnet 30, a detailed description of which' is believed to be unnecessary, as it forms no part of my present invention and is found in all receivers of the type being described. It is sutlicient to state that by sending varying numbers of alternating current impulses over the transmission 1ine the magnets 30 will control the escapement mechanism to properlyposition the character which it is desired to print relative to the printing mechanism.

The worm wheel 21 is driven by a worm.

31 rigidly mounted upon the counter-shaft 32. The counter-shaft 32 is driven from the drive shaft 17 by means of the gear 33 secured to the counter-shaft and the pinion 34 secured to the drive shaft 17.

The means for advancing the type wheel step by step in order to properly space the printed characters and for ret-racting the type wheel when it has 'reached the end of a line will now be described. This means com.- prises the type wheel moving shaft 35 which is provided with a helical groove 36 that engages with a tooth (not shown) on the type wheel carriage 37. The type wheel carriage isprovided with two spaced arms 38 which engage opposite ends of the hub 39 of the type wheel, whereby the type wheel is moved along the shaft 2O in the direction of movement of the type wheel carriage. The type wheel carriage also canries an inking roller 4() which is held against the periphery 'of the type wheel under the tension of the spring 41 in a manner well known. The means for driving the type wheel moving shaft to advance the type wheel comprises a worm 42 formed upon the sleeve 43 which is slidalbly mounted upon the shaft 32. At the outer end the sleeve 43 is provided with a toothed clutch member 44 which engages with a (zo-acting clutch member 45 The slee-ve 43 is urged upwardly to hold the clutch members 44 and 45 in co-acting relation by means of a pin 46 secured to the end of the arm 47. The arm 47 is pivotallv mounted upon the inner end of the stud shaft 48. The outer end of the stud shaft 48 is supported by the bracket 49 secured to the end pla-te 11. The pin 46 is urged upwarrdly by the spring 50, one end of which is secured to the arm 47 and the other end of which is secured to a collar 51 having a knurled disk 52 formed integral therewith. By rotating the disk 52 the spring 5() can be placed under any desired tension and then held under this tension by the set screw 53.

The worm. 42 meshes with a worm gear 54, which is rotatably mounted upon the stud shaft 55, one end of which is secured to the end plate 11 and the other end of which is supported by theV bracket 56. Surrounding the shaft 55 are a pair of springs 57 and 58 respectively. The adjacent ends of these springs are connected to the gear 54 by the screws 59 and 60 respectively. The inner end of the spring 58 is secured to the gear 61 by means of a screw 62 and the outer end of the spring 57 is secured to the end plate 11. It will be noted that both of these springs are placed under tension when the gear 54 is rotated in a couliter-clockwise direction in Fig. 3. The gear 61 meshes with pinimi 63 rotatably mounted upon the type wheel moving shaft 35. Rotatably mounted upon the shaft 55 and rigidly connected with the gear 61 are' a toothed cam 64 and an escapement wheel 65. The function of the cam 64 will be referred to later on. The escapement wheel 65 is controlled by an escapement lever 66 in a manner which will be described later on.

Firom the above description it will.` beclear that when the counter shaft 32 is rotated through the instrumentality of the pinion 34 and the gear 33 in the direction of the arrows in Figs. 2 and 6, the sleeve 43 and the worm 42 will rotate therewith due to the co-acting clutch members 44 and 45. 1t should be noted that the teeth on the clutch member 44 are beveled on both sides. i

and as a result the sleeve 43 will be moved' downwlardly until theI clutch members 44 and 45 are out of co-acting relation with each other. The beveled shape of the teeth on the clutch member 44 will permit the rotation of the clutch member 45 relative to the clutch member 44.

1f, while the springs 57 and 5S are under tension, the escapement lever 66 is oscillated, it will co-act with the esca-pement wheel 65 to permit the gear 61 to rotate through a naaste@ partial revolution, thereby rotating the pim ion 63 and the shaft 35 in a manner hereinl after described, a distance sufficient to move the type wheel through the proper spacing distance. This movement of the gear 61 relieves the tension of the springs 57 and 58, thereby causing the spring 50 to overcome the tension of these springs and force the clutch memlber 44 into co-acting relation with the clutch member 55, whereupon-the springs 57 and 58 are again wound up to such a tension as to displace the two clutch members relative to each other.

rlhs means for rotating the type wheel moving shaft 35 in the opposite direction in order to retract the type wheel comprises a worm gear 67 which is rotatably mounted upon the drive shaft 1'? and is held from longitudinal movement upwardly by means of the pinion 34. @n its lower side the gear 6'? is engaged by a friction clutch member 68 which is urged upwardly against the gear 67 by a. spring 69. rlhe lower end of the spring 69 is secured to a collar 'ZO which in turn is secured to theshaft 1'? by a set screw 7l. The means just described provides means for exerting a contant spring driving tension uponv the gear 6'2".. rlhe gear 67 meshes with a worm gear 72 rotatably mounted upon the shaft 35. The gear 72 is provided with clutch teeth 73 which co-act with the teeth of the clutch member ?4, which is slidably mounted upon the shaft 35. tnother clutch member 75 is also slidably mounted upon the shaft 35 and co-acts with a clutch 'member 'l' 6 formed integral with the pinion 63. The two clutch members 'Z4 and 'Z 5 are connected by means of bars 7? which are slidably mounted in ways in the guide bloclr .7 8. .'lhe guide member 'i8 is secured to the shaft 35 by a set screw 'Z3 From the above description it will appear that the clutch members 74 and 'l5 are slidably mounted upon the shaft 35 but are caused to rotate therewith by means of the guide block 78. When the two clutches are shifted so that the clutch member 'Z 5 engages the clutch member '7 6 and the escapement lever 66 is operated to' permit the escapernent wheel 65 to rotate the movement of the gear 61 will be transmitted to the pinion 63 through the clutch members 'Z 6, 'Z 5, the bars 'Z7 and the guide 'block 7 8 to the shaft 35. This movement of the shaft 35 will be in ya direction to advance the type wheel. lWhen, however, the clutch members are shifted so that the clutch members 'l5 and 7 6 are disengaged and the clutch member 74 engages the clutch teeth 'Z3 on the gear 72, the motion of the'gears 'Z2 will be trans- 'initted through the gear teeth 73, the clutch members 74, bars 7'? and the guide block 7 8 to the shaft 35, to rotate it in the opposite direction. rllle gear ratio of the retracting means is larger than that of the advancing be returned at a higher rate of speed than that at which it is advanced.

rl"he means which co-acts with the typeV wheel for printingl the selected characters comprises a platen secured to the ends of the arms 81. rlhe arms 81 are secured to the shaft 82 which is rotatably mounted in suitable 'bearings in the brackets 13 and 14. Secured to the left hand end of the shaft 82 is an arm 83, which carries a pawl 84 that projects in the path of the teeth 85 of the cam 64. As stated above, the cam 64 and the escapement wheel 65 are rigidly connected with the gear 6l to rotate therewith. 'lhe cam 64 is, however, so connected to the gear 61 that the type wheel is advanced to each new position before the teeth 65 have moved the arm 83 through a distance suiicient to bring the platen 80 at the upper ends of the arms 81 into printing relation with the type wheel. rlhe arm 83 has formed integrally therewith an extension 86 which is pulled downwardly by a spring 87, thereby holding the pawl 84 in contact with the cam 64 and also holding the platen in its retracted position.

rl`he means for feeding the paper between the type wheel and the platen comprises a pair of corrugated rollers 88, 89 which are respectively pivotally mounted upon the bradets 13 and 14 by means of pivot arms 90 and 91 carrying the pins 92 and 93 upon which the rollers 88, 89 respectively rotate. A pair of leaf springs 94 and 495 likewise secured to the brackets 13 and 14 respectively have their upper ends bearing against the pins 92 and 93 respectively, whereby the rollers 83 and 89 are yieldingly held against the paper the points where it passes over the corrugated rollers 96 and 97 which are rigidly mounted upon the shaft 98. 'lhe paper is guided upwardly between the platen and the type wheel to the paper feed rollers through the channel shaped guides 99 and 100 which confine opposite sides of the paper.

rlhe reference character 101 indicates a synchronism mechanism the structure and function of which is well known, as reference to the patent referred to above will show, and a detailed description of this portion of the receiver is therefore believed to be unnecessary. lt is sufiicient to state that this synchronizing mechanism is operated by the `arm 102 which carries the arm 103 rigidly secured thereto. r.lhe arm 103 is provided with an anti-friction roller 104 which engages the synchronism mechanism to lift the pin thereof from the helical screwthread 105.

rlhe means for driving the shaft 98 to which the paper feed rollers 96 and 9'? are -attached will now be described.A Secured to the lower end of the shaft 32 is a collar 106.

A spring 107 has its upper end connected to the collar 106 and its lower end connected to a friction disk 108, which engages bearing balls 109 carried in a suitable race in the uppei side of the pinion 110. The pinion 110 is rotatably mounted upon the shaft 106 and meshes with a. gear 111 which is secured to a shaft 112. The lower end of the shaft 112 rotates in a suitable 'bearing in the bed plate 10 of the machine and the upper end thereof rotates in a similar 'bearing in a bracket 113 extending inwardly from the end plate 11. Rotatably mounted in a bearing member 114, which is secured to the bracket 13, is a shaft 115 the lower end of which is connected to the upper end of the shaft 112 by means of a universal joint 116. The upper end of the shaft 115 carries a worm pinion 117 which meshes with a worm gear 118 on the end of the shaft 98.

From the above description it will be clear that when the gear 111 is rotated the shaft 98 will be rotated to feed the paper upwardly between the platen and the type wheel.

It is of course necessary that the paper feed mechanism should operate to move' the paper upwardly a distance equal to the space between the wheels at substantially the same time that the type wheel is retracted to start a new line. It is therefore convenient to haveY the line spacing mechanism and the retract-ing mechanism controlled by the same means. This means comprises a rock shaft 119, the forward end of which has a bearing in the bracket 120I secured to the end plate 11 and the opposite end rotates in a bearing in a bracket .121 secured to the bed plate 10. The' intermediate portion of 4the 'shaft 119 passes through the bracket113. At its forward end the shaft 119 carries an arm 122 which is rigidly secured thereto and provided at its upper end with a pin 123 which engages in an annular groove 124 in the clutch member 75. At its rear end the rock shaft 119 carries an armature 125 positioned in front of the poles of the electromagnet 126, and also an arm 127, which is pulled downwardly toward the bed plate 10 by means of a sp1ing1128 to hold the armature 125 away from the poles of the electromagnet 126. lVhen the electromagnet 126 is not energized the spring 128 will holdv the armature 125 away from the poles of the magnet 126 and will hold the arm 122 in the position where the clutch members 75 and 76 co-act with each other and the mechanism is properly Set to advance the type wheel, but when the magnet 126 is energized the armature 125 will be attracted against the tension of the spring 128 and the u per end of the arm 122 will be moved to tlie left in Fig. 1, thereby bringing the clutch member 74 into co-acting relation with the clutch teeth 78, and causing the type wheel to be retracted.

tated until the pin 131 engages the arm 129.

1,sos,sse

The downwardly depending arm 129 is rigidly secured to the shaft 119 and when the magnet 126 is not energized the lower end of thisA arm extends in front of a stop pin 130 carried by the gear 111, and thereby holds the gear against rotation. But when the electromagnet 126 is energized the resulting movement of the armature 125 will cause the lower end of the arm 129 to move out of the path of the pin 130 into the path of the pin 131, which is spaced slightly rearwardly in the direction ofthe rotation of the gear 111 from the pin 130. The gear 111 under tension of the spring 107 will be ro- When the electromagnet 126- is again deenergized the arm 129 will swing back to its original position, thereby releasing the pin 131, whereupon the gear 111 will make substantially a complete revolution until the stop 130 is again engaged by the arm 129. The ratio between the gear 117 and the gear 118 is such that the paper will be advanced the distance of a line space each time the gear 111 is rotated through a complete revolution.

The means for controlling the escapement lever 66 comprises a rock shaft 132 one end of which rotates in a bracket 133 and the other end of which rotates in a suitable bearing on the escapement magnet support 133. An armature 134 is rigidly secured to the shaft 132 and projects above the poles of the electromagnet 135. Thenever the electromagnet 135 is energized the escapement 100 lever 66 is actuated to permit the gear 61 to rotate throu h an angular distance corresponding to t e angular distance between the teeth on the escapement wheel 65, that is, a suii-cient distance to cause the type Wheel properly to space the printed characters.

The type wheels for printing telegraph receivers are usually provided with a plurality of characters whichthe transmitting station can select by sending the proper number of impulses over the line and through the escapement magnet, and are alsol provided with a blank space or'spaces 136 which the transmitting station can, by sending the proper number of impulses through the escapement magnet, position in front of the v printing platen. The type wheel is always brought to this position when it is desired to space the lines of the printed matter, and heretofore mechanical means of various kinds have been provided to actuate the retracting` mechanismwhen the type wheel is brought to this position. These mechanical means have alwavs embodied various levers or vibrating parts which are subject to continual Wear and which impose a certain amount of vibration upon the ad'acent moving parts of the mechanism an are therefore objectionable. In order to overcome these and other objections to the devices incasso heretofore employed, l mount a conducting: ringr 13? upon one end of the type Wheel shaft. lnserted in one end ot this ring is a narrow strip ot insulation 138. Bearing upon the ring 137 are two brushes 139 and 140., the brush 140 being so positioned as to hear upon the insulating strip 138 as the type Wheel shaft rotates or when the type Wheel shaft stops with this strip irrimediately below the end ot the brush 1-10. 1s shown in llig. 8, which will be referred to more in detail later on, it will be noted that the end of the brush 1a@ is turned downtvardly at 141 so as to be completely/'insulated :from the ringP 137 when the insulating strip 138 passes or is stationed beneath its end.,A rlihe insulation strip 138 is so positioned relative to the type Wheel shaft that it vvill lie immediately beneath the end ot the Ibrush 140 when the blank space on the type Wheel is opposite the platen, that is, when the type wheel is to be retracted.

Diiiiculty has heretoi'ore been experienced due to the tact that the type Wheel advancingmeans has been operated until the type Wheel carriage is at the extreme right-hand limit or its path ol travel. 1n 'this position the tooth of the carriage which rides in the groove 36 moves into the annular groove 1112 and there is a tendency Jfor this tooth to engage the adjacent shoulder on the shaft 35, Wearing this shoulder down and sometimes locking the shaft so as to throw the type Wheel and the type Wheel moving shatt out of phase with each other, and causing the letters to be printed one upon the other. order to overcome these diticulties 1 have provided automatic means for preventing,- the type wheel carriage trom overwinning the right han-d end oit the shaft. This means comprises a stationary switch contact 11i-41 and a movable contact 115, which is pivoted at 146, and is provided With an extension 147, which extends into the path of the type Wheel carriage. W hen the type Wheel carriage engages the inner end of the extension 117 it opens the contacts 11a, thereby causing energization of the retracting magnet 126 in a manner about to be described, and causing the type Wheel carriage to be retracted a slight amount until it no longer holds the contacts 115 and 141-1 open.

Having thus described the mechanical features ot my invention 1 will now describe the vcontrol circuits by means ot which the various parts of the receiver described above are controlled to operate in the proper sequence. f

Referring to Fig. 6, it will be noted that the escapement magnet 30 and the magnet 135, which will be referred to briefly as the printing magnet, although it also functions properly to space the printed letters, are connected in parallel by the conductors 150 and 151. rlfhese magnets are both connected in series with the switch comprising the contacts 14a and 1115, and also with the switching mechanism comprising the sleeve 131, the brushes139 and 1410 and the insulation segment or insert 138. W ith the parts in the position shown in Fig. 8 current'trom the line Wires 152 and 153 will ziovvthrough the conductor 151 to the brush 141-1, from the brush 111 to the brush 139, through the metal or the conductor ring 137, trom the brush 139 through the conductors 155 to the contact 1415, thence through the contact 1415 through the conductor 156 to the junction point of the conductors 151, Where the current divides and passes through the magnets 36 and 135 and back to the line wire 153 by the aid oi conduct-ors 150 and 151 and the conductor 157. 'llhe alternating current impulses sent from the transmitting station or stations connected with my improved receiver are produced by inserting la rotary commutator between a source oi direct current and the transmitting mechanism which determines the number or" alternations to be sent over the line Wires, and thereby determines the character selected to be printed. There is nothing novel about this transmittine" apparatus and it will not be described in detail. Ey those skilled in this art it is Well understood that when the coinmutator ceases to rotate only direct current is transmitted over the line `wires. l take advantage ot' this tact by s-o Winding the magnet 30 that it has comparatively high resistance but low reactance, and by winding the magnet 135 so that it has comparatively high reactance but lovv resistance. is a result of this construction ci the two magnets, when the alternating impulses are being sent over the line wires from the transmitting station the high reactance or the magnet 135 causes practically all or the cur-y rent to be shunted through the magnet 30, if ich has, as stated above, low reactance. This causes the escapement magnet control to position the type Wheel without energizing the magnet 185 sufficient to attract the armature 1341-. lihen, however, the commutator at the transmitting station ceases to send alternating impulses, the direct curi rent `which then ovvs through the line will choose to pass through the magnet 135 ot low resistance rather than through the magnet 3G ot high resistance. Consequently the armature 13e will be 4attracted and the printing and letter spacing1 mechanisms operated in the manner described above.

The reti-acting magnet 126 is also of comparatively high reactance and is consequently not a'ected by any alternating currents sent over the line wires. With the conducting ring 137 and the movable contact 115 in the positions shown in Fig. 8 the i magnet 126 is short circuited and but comparatively little current will -pass theregaa through, this current being insufficient to attract the armature 125 of this ma .et. When, however, the proper number of 1mpulses are sent from a transmitting station toposition the type wheel with the. blank space opposite the platen, the insulating 1nsert 138 will be positioned beneath the end of the brush 141 and this short circultmg circuit will -be opened. When, therefore, the commutator at the transmitting station comes to rest and direct current is sent over the line wires, this currentJ will pass through the magnet 126 and attract the armature 125 thereby placing the type wheel retracting mechanism into operation and causing the type wheel to be retracted to its normal position at the beginning of the line, where it is locked against any further movement f by the stop 158, which is secured to the shaft 37, as shown in Fig. 7, and which engages with a lugr 159 on the type wheel carriage,

thereby holding the type wheel moving shaft against further rotation. 'When the type wheel moving shaft is thus locked against rotation the gear 67 is held stationary relative to the friction clutch member 68 and the shaft 17.

During the operation of the recelver 1t 1s quite possible that the insulating strip 138 will pass beneath the brush 141 several times before the end of aline is reached. This ofcourse causes or tends to cause current to be sent through the magnet 126, but on account of the comparatively high reactance of this magnet and the fact that the short circuiting circuit remains open but an instant, the current does not have time to ibuild up sufficiently in the magnet 126 to attract the armature 125 and thereby cause the retracting mechanism to operate.

Fig. 8 also discloses the relation of the contacts 144 and 145 and the control mechanism. It will be clear that when the type wheel carriage engages the extension 147 and moves the contact 145 away from the contact 144, thereby opening the short circuit of the magnet 126, the latter magnet will be energized and move the type wheel carriage back to a point where the contacts 144 and 145 will again close, and thus Short circuit the magnet 126 and prevent any further retraction of the type wheel. By this means I prevent the type wheel and the type wheel carriage from-overrunning the right hand end of the type wheel movin shaft.l v

ile I have described my improvements in connection with a receiver operated by an electrical motor, and in which the type wheel carriage is moved by means of a shaft provided with a helical thread, and having various other features which are old, it is to be understood that my invention is not limited to receivers of this construction, but is capable of other adaptations and modifications within the scope of the appended' claims.

Having thus described my invention, what I claim as new and desire to secure vby Letters Patent of the United States is:

1. In a printing telegraph receiver the combination with a type wheel, of means coacting with said type wheel to print the characters thereon, means for rotating said type wheel, means for controlling the rotating means to present the proper characters to the printing means, comprising an electromagnet, a type'wheel movin shaft for moving said type wheel, means or rotating said type wheel moving shaft in one direction to advance said type Wheel and means for rotating the type Wheel moving shaft in the opposite direction to retract said type wheel, means for controlling the rotation of said type wheel moving shaft to advance said type wheel comprising an electromagnet, means for controlling the rotation of said ty e wheel moving shaft to retract said type w ieel, comprising a magnet, a conducting ring provided with a narrow insulation insert connected to rotate in synchronism with said type wheel, a pair of brushes bearin on said ring in such a position that said insulation insert passes beneath one of saidbrushes upon the 4rotation of the conducting ring, a vswitch positioned to be opened by said type wheel when said type wheel has advanced to a predetermined position, means for connecting said first two v magnets with each other, and in series with tions for shunting said last named magnet around said ring, brushes, and switch.

2. In Va printing telegraph receiver the combination with a type wheel of means coacting with said type wheel toiprint the characters thereon, means 4for rotating said type wheel to present the ydesired type to said printing mechanism, comprising an electromagnet responsive to alternating cur'- rent, means for advancing .said type wheel to space the printed characters, an electromagnet unresponsive to alternating current for controlling said printing and advancing means,v means for retracting said type wheel comprising an electromagnet, means for connecting said two first magnets, a switch operatively connected with said type wheel, a second switch, automatic means for opening said second switch when said type wheel is advanced to a predetermined position, means for connectln said switches in series with each other and 1n series with said two first-named magnets, andl means for shunting said last-named magnet about said switches.

3. In a printing telegraph receiver the combination with a type wheel of means coacting with said type wheel to print the characters thereon, means for rotating saidr ascenso i type wheel to present the desired typeto said printing mechanism, comprising an electromagnet responsive to alternating current, means for advancing said type wheel to space the printed characters, an electroinagnet unresponsive to alternating current 'for controlling said printing and advancing means, means for retracting said type wheel comprising an electromagnet, means :tor connecting said two tirst magnets, a switch operatively connected with said type wheel at all positions oi.E said type wheel, means for connecting said switch in series `with said two first-named magnets, and means tor shnnting said last-named magnet alo-out said switch. I

Ll. ln a printing telegraph receiver the combination with a type wheel oi' means coacting with said type wheel to print the characters thereon, means for rotating said type wheel to present the desired type to said printing mechanism, comprising an electromagnet responsive to alternating current, means for advancing said type wheel to space the printed characters, an electromagnet unresponsive to alternatingi current for controlling said printing and advancing means,

means for retracting said type wheel corrprising an electromagnet, means :tor connecting said two nrst magnets in parallel, a switch, automatic means ier opening said switch when said type wheel advanced to a predetermined position, means -or connecting said switch in series with said two iirst-named magnets, and means for shunting said last-named magnet about said switch. c

o. ln a primtincn,` telegraph receiver the combination with a type wheel oi means coacting with said type wheel to print the characters thereon, means tor rotating said type wheel to present the desired type to said printing mechanism, comprising an electromagnet, means for advancing said type wheel to space the printed characters,`

an electromagnet for controlling said printing and advancing means, means for uretracting said type wheel comprising an electromagnet, means tor connecting' said two first magnets in parallel, a switch controlled hy said second-named magnet, means tor connecting said switch in series with said two irst-named magnets, and means for connecting said last named magnet in shunt about said switch.

6. ln a printing7 telegraph receiver the combination with a type wheel of means coacting with said type wheel to-print the characters thereon, means ior rotating said I type wheel to present the desired type to said printing mechanism, comprising an electr magnet, means tor advancing said type wheel to space the printed characters, an electromagnet for controlling said printing and adn vancing means, means tor retracting said type wheel comprising an electromagnet, means '.torconnectm said two first meets,

.a switch controlled y ,the rectilinear movenient of said type wheel, means for connecting said switch in series with' said two tiret named magnets, and means for connecting said last named magnet in shunt about said switch.

"3'. :in a printing telegraph receiver the combination with a type wheel of means tor rotating said type wheel comprising an electromagnet responsive to alternating current, means tor advancing said type wheel to space the printed characters, comprising an electromagnet unresponsive to alternating current, means :tor connecting` said' magnets in parallel, means for retracting said type wheel comprising an electromagnet, a switch for controlling said last named magnet, connected in series with said two first-named magnets, and means for connecting said lastnamed magnet in shunt around said switch.

8. in a printing telegraph receiver the combination with a type wheel of means for I rotating said type wheel comprising an electromagnet, means tor advancing said type means for retracting said type wheel comi prising a slow acting electromagnet, means tor connecting said last named magnet in series with said first-named magnets, means for short circuiting said last named magnet, the said last named means comprising a switch and means controlled hy said firstnamed magnet for operating said switch.

l0. [i printing telegraph receiver comprising a type (wheel, means :for rotating said type wheel to select the proper characters to be printed, comprising an electromagnet, means for advancing said type wheel to space the printed characters, and automatic means ior preventing said type wheel from advancing beyond a predetermined position, the said automatic means comprising an electromagnet, means ior short-circuiting the terminals of said magnet comprising a switch, and means for opening said switch when said type wheel is advanced to a predetermined position.

il.' ln a printing telegraph receiver the combination with a type wheel, oi means co-acting with said type wheel to print the characters thereon, means for feeding paper past said t pe wheel, means for rotating said type whee means for `controlllng the rotating means to present the proper characters to the printing means, comprising an electromagnet, a type wheel movm shaft for moving said ty e wheel, means or rotating said type whee moving shaft 1n one dlrection to advance said type wheel and means for rotating the type Wheel moving shaft 1n the opposite direction to retract said type wheel, means for controlling the rotation of said type wheel moving shaft to advance said type wheel comprising an electromagnet, means for controlling the rotat1on of said ty e wheel moving shaft to retract sald type w eel, and for controlling sa1d paper feeding means, comprising a magnet, a conducting ring `provided with a narrow lnsulation insert connected to rotate in synchronlsm with said type wheel, a pair of brushes bea r ing on said ring in such a position that said insulation insert passes beneath one of s ald brushes upon the rotation of .the conductlng ring, a switch positioned to be opened by said type wheel when said type '.wheel has advanced to a predetermined positlon, means for connectin said first two ma ets in par allel with eac other, and in series with said ring, brushes and switch, and connections for shunting said last named magnet around said ring, brushes, and switch.

12. In a printing telegraph receiver the .combination with a type wheel of means coacting with said type wheel to print the -characters thereon, means for feedlng paper past said type wheel, means for rotatlng sald type wheel to present the desired type toV said printing mechanism, comprislng an electromagnet, means for advancing said type wheel to space the printed characters, an electromagnet for controlling said printing and advancing means, lmeansfor retracting said t pe wheel, and for actuating said paper fee ing means, comprising an electromagnet, means for, connecting said two first magnets in themovement of said type wheel, means for connecting said switch in series with said vtwo first-named magnets, and-means for conparallel, a switch controlled by the said magnet being so slow acting that it will not operate except/when the type wheel comes to rest with the switch open.

14:.V The combination with a printing telegraph receiver of a type wheel shaft, a type wheel splined to said shaft, means for rotating said shaft, means for advancing the said type wheel space b s ace, means for retracting said type wheel? comprising a magnet and a switch for short-circuitlng sald magnet, comprising a contact member connected to said type wheel shaft to rotate in synchronism with said type wheel, a switch member bearing on said contacting member, and means for momentarily unsealing said switch mem'ber from said contact member once during each revolution of said type wheel shaft.

15. VThe combination with a printing telegraph receiver of a type wheel, means for rotating said type wheel, means for advancing said type wheel space by space, means for retracting said type wheel, comprising a magnet and a switch for short-circuiting said magnet, comprising a contact member connected to rotate in synchronism with said type wheel, a switch member bearing on said contact member, and means for momentarily unseating said switch member from said contact member once during each revolution of said type wheel. y

In witness whereof, I hereunto subscribe my name this 6th day of May, 1918.

HARRY V. GROTJOHANN. Witnesses:

GEORGE D. Rosa, EARL F. PIERCE. 

